Method of forming worm gears



W. E. 06KA METHOD 0F FORMING WORM GEARS.

APPLICATION FILED MAY II\ I9I4 @merrain nur Winnmn entre Boon, orromano, onto, nssreuort vro 'ran noon WORM GEAR. coMrANr,

ufr o "WEGE, l

F CLEVELAND, OHI, A CORPORATION F 0R10.

METHUD 0F FRMING WRM-GEAHS.

Application l'ed May il, le le.

To all whom it may concern Be it known that l, VtfnmrAM EMIL Boon,

a citizen of the United States of America,4

residing at Toledo, in thev county ofLucas and State of Ohio, haveinvented certain new and useful improvements in Methods of FormingWorm-Gears, of which the following is a speeitication, reference beingyteeth from .the point orentering engagement to the point ofdisengagement; lt 1s a further object te obtain a simple method ofproducing a Worm of this character.

ln the drawingsr- Figure l is a side elevationio the worm, in'connection with the cutter and coperating mechanism for .controlling thesame;

Fig.' 2 is a view at right a u les to Fig. l; i

Fig. 3 isa side elevation l the Worm-,in modied construction; and l v,

IFig. d is a cross section..

The particular type of' Worm gearing to which my improved constructionis applin cable is that in which the worm Wheel is provided with rollerteeth having. their axes parallel to the axis of the Wheel andprojecting laterally from the tace of the-Wheel. The Worm is arranged atthe side of the Worm gear with its axisV transverse to the gear axis,and in operation the roller teeth successively engage'the spiral faceoi' the Worm', a pluralityv of the r'olls being in engagement with thesamek face at the same time. By reason ofthe circular orbit of theroller teeth, the direction of movement varies in angular relation tothe axis of the Worm, and consequently the successive convolutions 'ofthe' spiral are not of theanle pitch. Furthermore, the roils not onlymove longitudinally-of the Worm but transversely with respect to theaxis thereoie and also in and out With respectto the periphery of theWorm. rllhis variation renders the formation of the Worin' by methodsheretofore employed exceedingly diiicurlt, but by my improved method the`difficulties are overcome and the work may be performed with er.- trcmeaccuracy.

As shown in Fig. l, A is the Worm, formed Specification of LettersPatent.

Patented June 3, 1919.

serial no. sarees.

with its s 'ral face of progressively chang* ing pitch, so that thedistance between suecessive convolutions is correspondingly chan'ed. Tocut the 'Worm in this form it is eceary that the cutting tool shouldmove not only longitudinally with respect to the axis orf thevvormduring the rotation there of, but also laterally. lrlfhis I accomplishin a simple manner by mounting the rotary cutter B upon a suitablecarrier, such as the disk C, Which rotates about a eenterD,

the radius of the path through which the cutter passes corresponding tothe radius of the gear in cooperation with Which the Worm is to be used.The disk C is also rotated simultaneously with the rotation of the Wormblank and in predetermined timed relation thereto, as by means of timedconnecting gearing E between the Worm arbor F and mechanism, such asWorm gearing G, for

rotating the disk. As a consequencer the groove H cut by the rotarycutter B will be of a Width. corresponding to the diameter of saidcutter, but the faces oi' said groove will vary in pitch, as abovedescribed. f

Wheredesired, Worms may be cut by my improved method so as to beprovided With a plurality of separate grooves, such as H- H2 Fig. 3..7ilhese are cut in the saine manner as previously described and in useWill coperate With the .roller teeth of the gear to maintain a largernumber of said teeth in action at the same time.

As indicated inliligza, the grooves in the Worin progressively increa ein depth from the point of entrance toward the longitudinal center andthen decrease in depth from this oint to the point of disengagement.

at l claim as my invention is l. The method ci cutting Worms with thespiral face thereofL of progressively changing pitch, comprising therotation of the Worm blank, and the simultaneous movelment yof thecutterionitudinall and transing ptd), comusng the otaton of the: wom)blank about th@ agis thaw/Q12 and th@ simultaneous movameut 02E theuttel'lin @Ik gztgemnt with said blank thrtmgh a, cit cular orbit at on@side G' the, :mis of said. blank and pzufzlu to a 'plane tangent to theperphe'y thmeot'.

4v. The mcthud of cutting; Wol'ms with the splint fmt@ thereof ofprogx'essvay chsmgging pitch, conlplfisngg the tot 'on of th@ worm blau]l1: about the uxs txweot, @nfl t smutnneous mow/munt uit the Cutts): inu, circulan' orbit fm at plans at wn@ Sift@ of the, axis of the blank:md into und mt from Qugagon'lcnt therewith A (i, The method @it cuttinga Worm, tihah conssts in lotat'ng the Work? rotating' cuttel inoperativ@ proximity to such work,

